Summary of MSSL/UCL Cosmology

Transcription

1 Summary of MSSL/UCL Cosmology Jason McEwen, Tom Kitching & Mark Cropper

2 MSSL Cosmology Mark Cropper head of the Astrophysics Group Two (relatively) new cosmology lecturers: Tom Kitching, Jason McEwen Strong involvement in Euclid mission As part of new injection of people (faculty, postdocs & PhD students) we hope to enhance existing links with other London Cosmology groups and develop new collaborations

3 Astrophysics Group Members 9 HEFCE-funded staff: Graziella Branduardi-Raymont, Mark Cropper, Ignacio Ferreras, Daisuke Kawata, Tom Kitching, Jason McEwen, Mat Page, Kinwah Wu, Silvia Zane 3 STFC-funded research postdocs: Steffano Pasetto, Myrto Symeonidis, pending 2 EPSRC-funded research postdocs: Start early 2015 (to be advertised soon) 5 UK Space Agency-funded mission-orientated science postdocs: Alice Breeveld, Paul Kuin, Sami-Matias Niemi, George Seabroke, Vladimir Yershov 8 PhD students Just started: Jennifer Chan, Denis Gonzales, Ellis Owen Jason Hunt, Susan Hutton, Idunn Jacobsen, Alvina On, Megan Whewell Just completed: David Barnes, Rob Grand, Jason Rawlings, Ziri Younsi

4 Astrophysics Group Members Kinwah Wu Tom Kitching Graziella Branduardi- Raymont Mat Page Mark Cropper Alice Breeveld George Seabroke Ignacio Ferreras Jason McEwen Vladimir Yershov Daisuke Kawata Others Megan Whewell Jennifer Chan Sami- MaHas Niemi Myrto Symeonidis

5 Main Science Fields Compact Objects Neutron stars Gamma-ray bursts Black holes (supermassive) Galaxy Evolution Star formation history and black hole growth in UV, optical and Infrared Galaxy structure, galaxy modelling Radiation Transfer Theory Polarised transfer in highly gravitationally curved regimes (photons, neutrinos) Cosmology Origin and evolution of cosmological magnetic fields Nature of Dark Energy and Dark Matter Early Universe Cosmology Radio Interferometry and the Epoch of Reionization

6 Cosmological Magneto-Genesis How large-scale magnetic fields originated and developed and what their roles were in cosmological structural formation are unresolved issues A new GCMHD+ code developed for cosmological magnetohydrodynamic simulations We investigate how large-scale magnetic fields imprint signatures in sky polarisation and develope a cosmological polarised radiative transfer code and a covariant algorithm to interface it with the GCMHD+ code MHD simulations of the evolution of large-scale (30 Mpc 3 ) magnetic fields from red shifts z = 0.9 to z = 0 (from left to right) using our GCMHD+ code Our studies provide a solid framework for the analyses of future MWA and SKA data, give proper interpretations of observations and enable more meaningful comparisons with the predictions of cosmic magnetism models

7 Dark Energy Most dark energy informahon comes from small scales: Amplitude of clustering of dark mater Linear AnalyHc The Promise Pitfall of Weak Lensing Non- Linear N- body PredicHons Dark Energy Sensi.vity Varying dark energy equa.on of state by 20% 100 Mpc large- scales 1 Mpc Unknown physical effects? 0.01 Mpc small- scales

8 Dark Energy Linear scales are consistent with LCDM Small scales are not consistent with LCDM: either LCDM is wrong or we don t understand small scales Large Scales Small Scales dark energy equahon of state Planck+Lensing ΛCDM 1σ, 2σ contours ΛCDM Planck+Lensing MaTer density Kitching et al. (2014)

9 Cosmic microwave background (CMB) Anisotropic cosmologies Early Universe Cosmology Topological defects (cosmic strings and textures) Dark energy Inflation and non-gaussianity Planck Bianchi models Planck CMB observahons

10 Radio Interferometry and EoR Square Kilometre Array (SKA) Software Data Processor (SDP) design study Radio interferometric imaging with compressive sensing Observing the Dark Ages and Epoch of Reionization (EoR) SKA SKA State- of- Art Compressive Sensing Observing the Epoch of ReionizaHon

11 Astrostatistics & Astroinformatics Astrostatistics: exploit statistical approaches to extract scientific information from observational data Bayesian statistics Path integral methods Machine learning Fast algorithms and big-data Astroinformatics: exploit information theory to extract scientific information from observational data Wavelets Compressive sensing Machine learning Fast algorithms and big-data Cosmological observations live on spherical manifolds Connections between astrostatistics and astroinformatics

12 MSSL Astro Missions Science is underpinned with strong links to space instrument teams Operating missions: XMM-Newton (OM and RGS) [1999] Swift (UVOT) [2004] Herschel (SPIRE) [2009] Gaia (RVS) [2013] Awaiting launch: James Webb Space Telescope (NIRSpec) [2018] Under Development Euclid (VIS) [2020] PLATO [2024] Athena+ [2028] Proposed: M4 LOFT [2023] high energy astrophysics (compact objects) galaxy structure and evoluhon cosmology planets

13 Euclid Euclid Weak Lensing major focus of cosmology group long term from now to (data and post-mission) MSSL leads both the Instrument for weak lensing (VIS; Cropper) and Instrument Scientists (Niemi) co-leads science for for weak lensing (Weak Lensing Science Working Group; Kitching)

14 Involvement in External Experiments Planck SKA LSST CFHTLenS KiDS

15 Where to find more MSSL Astrophysics: MSSL: MSSL Astro Blog: msslastro.wordpress.com Late Universe Blog: lateuniverse.wordpress.com Personal Websites: